Simplify the following expression: $k = \dfrac{6fg + g}{6g^2} - \dfrac{4fg + g}{6g^2}$ You can assume $f,g,h \neq 0$.
Solution: Since the expressions have the same denominator we simply combine the numerators: $k = \dfrac{6fg + g - (4fg + g)}{6g^2}$ $k = \dfrac{2fg}{6g^2}$ The numerator and denominator have a common factor of $2g$, so we can simplify $k = \dfrac{f}{3g}$